U.S. Authorities say Ilya Zhitomirskiy, the 22-year-old Soviet-born co-founder of the Diaspora social network, died in California during the weekend.
Local media reports indicated that Zhitomirskiy may have committed suicide.
The San Francisco coroner has said that it will take several weeks to determine the cause of Zhitomirskiy's death.
Zhitomirskiy emigrated from the Soviet Union to the United States as a child with his parents.
He was one of four U.S. college students who launched Diaspora last year in a bid to win fans as an easier, more private alternative to social networking giant Facebook.
Diaspora opened to software developers in September last year, and a version of the online network went public two months later.
compiled from agency reports